'use strict';

function even_to_letter(collection) {
  var word = []
  //在这里写入代码
  for(var i=0;i<=collection.length;i++){
    if(collection[i]%2==0){
      var m = String.fromCharCode(97+collection[i]-1)
      word.push(m)
    }
  }
  return word
}

module.exports = even_to_letter;
